angular.module('datatablesDirectives', []).directive('datatable', function ($http) {
    return {
        // I restricted it to A only. I initially wanted to do something like
        // <datatable> <thead> ... </thead> </datatable>
        // But thead elements are only valid inside table, and <datatable> is not a table.
        // So.. no choice to use <table datatable>
        restrict: 'A',

        link: function ($scope, $elem, attrs) {
            var options = {};

            // Start with the defaults. Change this to your defaults.
            options = {}

            // If dtOptions is defined in the controller, extend our default option.
            if (typeof $scope.dtOptions !== 'undefined') {

                angular.extend(options, $scope.dtOptions);
            }

            // If dtoptions is not declared, check the other options
            if (attrs['dtoptions'] === undefined) {

                // Get the attributes, put it in an options
                // We need to do a switch/case because attributes does not retain case
                // and datatables options are case sensitive. Damn. It's okay! We need to detect
                // the callbacks anyway and call it as functions, so it works out!
                // I put what I needed, most of my settings are not dynamics except those 2.
                for (property in attrs) {
                    switch (property) {
                        // This is the ajax source
                        case 'sajaxsource':
                            options['sAjaxSource'] = attrs[property];
                            break;
                        // This is the ajax data prop. For example, your result might be
                        // {code: 200, data: [ .. ]} -> in the case, sAjaxDataProp is data
                        case 'sajaxdataprop':
                            options['sAjaxDataProp'] = attrs[property];
                            break;
                    }
                }
            } else {
                // If dtoptions is declare, extend the current options with it.

                angular.extend(options, $scope.dtOptions);
            }

            // Just some basic validation.
            if (typeof options['sAjaxSource'] === 'undefined') {

                throw "Ajax Source not defined! Use sajaxsource='/api/v1/blabla'";
            }

            // for Angular http inceptors
            if (typeof options['fnServerData'] === 'undefined') {
                options['fnServerData'] = function (sSource, aoData, resultCb) {
                    $http.get(sSource, aoData).then(function (result) {
                        resultCb(result.data);
                    });
                };
            }

            // Get the column options, put it in a aocolumn object.
            // Obviously, mdata is the only one required.
            // I personally just needed those 3, if you need other more feel free to add it.
            // mData also accepts a function; I'm sure there's a more elegant way but for now
            // it detects if it's a function, and if it is, do it.
            options.aoColumns = [];

            // Get the thead rows.
            $elem.find('thead th').each(function () {
                var colattr = angular.element(this).data();
                //console.log(colattr);
                //console.log('demodeo');
                // Detects if it's a function. Must exist in scope.
                if (colattr.mdata.indexOf("()") > 1) {

                    // Simple one-liner that removes the ending ()
                    var fn = $scope[colattr.mdata.substring(0, colattr.mdata.length - 2)];

                    // Throw an error if it's not a function.
                    if (typeof fn === 'function') {
                        options.aoColumns.push({
                            mData: fn,
                            sClass: colattr.sclass,
                            bVisible: colattr.bvisible,
                            mRender: colattr.mrender
                        });

                    } else {

                        throw "mData function does not exist in $scope.";

                    }
                } else {
                    //console.log('<1?');
                    options.aoColumns.push({
                        mData: colattr.mdata,
                        sClass: colattr.sclass,
                        bVisible: colattr.bvisible,
                        mRender: colattr.mrender
                    });

                }
            });

            // Load the datatable!
            $elem.dataTable(options);
            //console.log(options);

        }
    }
});